<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>添加伪元素</title>
</head>
<body>
    <div class="title">用Chrome学编程</div>
    <style>
        .title::before{
            content: "《"
        }
        .title::after{
            content: "》";
        }
    </style>
</body>
</html>